1. Field
The field of the invention is disc brakes for tracked vehicles, and more particularly those associated with differentials of such vehicles.
2. Prior Art
Differentials have been extensively used to transmit power from engines of tracked vehicles to track drive shafts. Vehicle steering has been accomplished by overdriving the track drive shaft on the side of the vehicle away from the direction of turn, by braking the drive shaft on the side toward the turn, or by a combination of both. Some differentials have also utilized internal braking devices to slow the rotation of the power output shaft linked with the track drive shaft on the side toward the turn, while increasing the rotation of the power output shaft away from the turn. These braking devices are distinctly disadvantageous because of contamination of differential fluid from wearing brake parts, and because of their inaccessibility for repair purposes. Some differentials have utilized internal braking gears with connecting shafts extending outside the differential housing. A type of such a differential is disclosed and claimed in Austrian Pat. No. 296,368. Various types of friction braking devices have been suggested and sometimes actually employed for use on the braking axles outside the differential housing, including friction disc types, which are claimed in the above mentioned patent generally as a preferred brake type without any mention of cooling provisions. However, none of these prior brakes, including the disc types, have been capable of continued use without frequent repair and replacement of friction components because they have lacked adequate provisions for cooling of these critical components. Cooling is essential because the brakes are in almost constant use when the vehicle is being operated.
Liquid cooled disc brakes have been disclosed for directly braking the wheels of vehicles other than tracked vehicles, for example, in U.S. Pat. Nos. 2,940,549, 2,955,682, 2,971,612, and 2,928,504. However, none of these have been adapted for use in conjunction with a vehicle differential, and especially not with the differential of a tracked vehicle.